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    <title>Document</title>
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<body>

    <div class="a">
        <p>11</p>
        <span></span>
        <h3>3</h3>
        <span></span>
    </div>

    <ul>
        <li>1</li>
        <li>2</li>
        <li>3</li>
    </ul>

    <ol>
        <li>11</li>
        <li>22</li>
        <li>33</li>
    </ol>

    <script src="../js/jq_v2.js"></script>

    <script>
        $('p').parent().css('color' , 'red').hide() 


        $('p').siblings().css('color' , 'blue');

        // $('p').index().css() 


        console.log($('p').index());   // 0
        console.log($('h3').index());  // 2

      
        $('ol li').eq(1).css('color' , 'yellow');


    </script>
    
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